In the recent years, computer technologies have brought hospitals and clinics the advanced use of the computer systems. At most large hospitals, the hospital information system has been installed. Similarly, the medical imaging devices have been widely used and include X-ray computer tomography (CT) scanners, Positron Emission CT Scanners, magnetic resonance imaging (MRI) devices and digital X-ray devices.
Despite the widespread use of imaging devices, the stored image data is not managed by a computer system at many institutions. Rather, the medical images are still viewed on traditional hard-copy media such as films. For a traditional medical image management, the following problems are associated. It generally takes some time to retrieve a desired hard copy. As a result of a large storage volume, it requires a large physical storage area, and a film is often lost.
To solve the above problems, the picture archiving and communication system (PACS) has been developed. For example, TOSPACS view (TWS-2000) is commercially available from Toshiba Medical Systems. In general, the PACS enables that the medical imaging data is stored in a database at a file server or other storage devices while a desired image is accessed on line via network from an office, an outpatient clinic and a hospital.
Furthermore, the use of the medical image is combined with the computer aided diagnosis (CAD). A certain portion of the scanned image is processed by a predetermined software program to isolate an abnormal area. In the above described use, the PACS is used to obtain the desired image data via network from the file server for preparing an input to the CAD. Thus, the environment includes a file server at every medical facility for storing imaging data that has been collected from medical imaging devices such as an X-ray device, a CT scanner and a MRI scanner. The environment also includes a central facility where a predetermined set of processing software is centrally deposited and managed. For example, the software processes the scanned image data to generate a three-dimensional image, a combined image of selected portions and arranged images. Lastly, the environment further includes a cluster of distributed viewing terminals or consoles where an authorized user requests a specific imaging data and issues a desired post-scanning processing command via the network for further processing the requested imaging data.
In the above described distributed environment, the system is not responsive in certain situations. In response to a request to process a specified imaging data set from a viewing console, a central control device determines a file server where the specified imaging data is stored and transmits the file server a request to transfer the specified imaging data to the central device. The central device performs a specified post-scanning process on the transferred imaging data and transmits the processed imaging data back to the viewing console. Because of the voluminous nature of the medical imaging data, a large amount of data is transferred over the network between the file server and the central device. Although the imaging data can be transferred in advance of a certain post-scanning process to minimize the response time, it is not possible to anticipate every post-scanning process. As a result of the increased network traffic, a response time at the viewing console becomes undesirable.
In relation to the prior art, the following disclosures teach some specific techniques for improving some aspects of the above described problems. Japanese Patent Publication 2002-230165 discloses a picture archiving and communication system. After access from a viewing terminal is authorized at an image data storage facility, the viewing terminal receives not only requested medical imaging data in a compressed format but also a predetermined viewing program. The downloaded software such as a JAVA applet enables only an authorized user to view a requested medical image by decoding and decompressing the downloaded imaging data. The authorized user is able to generate a report and upload it in an encoded and or compressed format. After the access is complete, the downloaded JAVA applet is disabled or deleted at the viewing terminal.
Japanese Patent Publication 2003-102721 discloses a picture archiving and communication system. Medical imaging data is locally collected at a client device or a modality and is centrally stored in a file server via a network. A user retrieves a medical image from the file server for viewing at a local terminal that is connected to the file server via the network. During the viewing, the user issues a post-scanning process command including parameters indicative of certain commands such as noise reduction or edge enhancement of the X-ray scanned imaging data. In response to the post-scanning process command, the system determines a client device that currently has the lightest processing load and is capable of processing the requested post-scanning process. The selected client device receives the specified imaging data from the central file server. Since each one of the client devices has a local copy of the processing software programs, it performs the specified post-scanning process. The processed image data is delivered and stored at a requested storage address in the parameter.
Japanese Patent Publication Hei 8-315119 discloses a picture archiving and communication system. Medical imaging data is locally collected at a client device or a modality and is centrally stored in a file server via a network. To avoid a duplicate medical image at a central storage unit, an incoming image for storage is checked based upon a certain combination of predetermined sets of criteria such as an ID number attached to the image, a time stamp of the image and or a difference between images. The substantially reduced duplicate image data enables the storage unit to efficiently store the image data as well as efficiently transfer the requested imaging data over the network without a duplicate.
Despite the above described prior art attempts, the PACS remains to be desired for optimizing the post-scanning process command. Since the PACS environment is not static and the user priority varies, the PACS should be able to optimize the post-scanning processing in a flexible and a cost-efficient manner without increasing network traffic and response time.